In chair and desk construction, frame members are frequently used in the form of tubular metal members such as tubes having a generally circular configuration. They have the advantage of light weight and in the case of tubular construction of a circular configuration, they may be bent to form corners or angles without collapsing the tube using known technology.
Desks and like articles are also constructed using rectangular or square tubing. Compared to circular tubing, rectangular tubing generally possesses higher strength characteristics and is more readily adaptable to a variety of construction features. When corners or angles are encountered in such furniture construction, various arrangements are used. For example the rectangular tubing is cut and either a corner adapter used or alternately, the tubing cut at a defined angle and welded to adjacent tubing at a similar angle. Another alternative is to bend the tubing against a flat face.
There are some situations where rectangular or other polygonally shaped tubing would be desirable, if it could be utilized in a manner similar to circular tubing where the latter is readily bent to be used around corners. While rectangular or square tubing can be bent by bending against the flat faces, one problem that has existed heretofore is that the rectangular or square tubing could not be bent on the diagonal so that it would present a uniform and aesthetically acceptable structure for use in furniture construction.